Upgrade Domino and Notes version 4.62 to version 6.5

Hello Everyone. I’m quite new to Lotus Domino and Notes. In 2 weeks time, I’ll be upgrading a system running on Domino 4.62 together with Notes Client to version 6.5. I need advice on how to go about this and anything to consider or to look out for. Can I upgrade it straight away to 6.5 or do I need to update anything like patch or do i need to go to version 5 first or anything. Thanks in advance.